High pressure fluid pumps are used in many industrial applications. In particular, many modern coating and insulating applications require consistent high pressure delivery of two components that react quickly with each other. Such applications typically require delivery of the two components, commonly referred to as “A-side” and “B-side,” simultaneously to a delivery device such as a sprayer where the components are mixed immediately prior to being discharged. Apparatus for delivering multiple-components to a nozzle apparatus are sometimes referred to as proportioners. Applications that require delivery of multiple components include plural-component polyurethane spray foam, tank and pipe coatings, adhesives and caulk, rim and band joist applications and the like.
Spray polyurethane foam (“SPF”) has become popular for its insulation value and air barrier qualities. The plastic material comes in several basic types, including: ½-lb, 2-lb and 3-lb. These types are used in insulation applications as barriers in buildings, for example. These foams can also help control condensation within buildings and have other environmental benefits.
These ½-lb, 2-lb, and 3-lb SPF are made from blended systems of polyol resins, catalysts, surfactants, fire retardants, and blowing agents on the B-side, with polymeric MDI (methylene diphenyl diisocyanate) on the A-side. The difference between SPF types is in how these materials are formulated.
Two-component polyurea spray elastomers are useful for their fast reactivity and relative insensitivity to moisture, making them ideal for coating large surface area projects, such as secondary containment, manhole and tunnel coatings, and tank liners. Excellent adhesion to concrete and steel can be achieved using suitable primer and surface treatment, as is known in the art. New two-component polyurethane and hybrid polyurethane-polyurea elastomer systems have been developed and used for spray-in-place load bed liners and the like. This technique for coating pickup truck beds and other cargo bays creates a durable, abrasion resistant composite with the metal substrate, and eliminates corrosion and brittleness associated with drop-in thermoplastic bed liners.
Polyurea compositions have been used as components of liquid pavement marking compositions, as described in U.S. Pat. No. 6,166,106 to Purgett et al. The binder of the pavement marking compositions described therein is prepared from a two-part system that includes an amine component and an isocyanate component. The composition described therein contains reflective elements to provide visibility and reflectivity to the pavement markings over an extended length of time.
Polyurea spray compositions have also been used for coating or lining materials. For example, U.S. Pat. No. 5,405,218 to Hyde-Smith discloses fast curing materials that can be applied directly to composite and metal surfaces.
With the increasing demand for two component systems such as polyurea, polyurethane, including polyurethane foams and the like, there is a need for improvements in the equipment for delivering the components for such systems.